1. Technical Field
The present disclosure relates to a display device.
2. Description of the Related Art
Demand has recently increased for display devices for use in, for example, mobile electronic apparatuses, such as mobile phones and electronic paper. In a display device, each pixel includes a plurality of sub-pixels that output light of colors different from one another, and display of the sub-pixels is switched on and off so that the pixel displays various colors. Techniques (for example, that disclosed in Japanese Patent Application Laid-open Publication No. 2007-94089 (JP-A-2007-94089)) have been developed in which the display device includes white pixels as fourth sub-pixels in addition to the conventional red, green, and blue sub-pixels. Such techniques can improve display quality by adding the white pixels.
For example, JP-A-2007-94089 describes a liquid crystal display device that separately includes a region constituted by red, green, and blue sub-pixels and a region constituted by red, green, blue, and white sub-pixels, and thus, minimizes design cost while improving the display quality.
However, the region constituted by the red, green, blue, and white sub-pixels has more components, such as wiring for driving the sub-pixels, than those in the region constituted by the red, green, and blue sub-pixels. For example, in JP-A-2007-94089, a backlight emits light to display an image. Consequently, the region constituted by the red, green, blue, and white sub-pixels has a smaller aperture ratio than that of the region constituted by the red, green, and blue sub-pixels by a ratio occupied by the wiring. Due to this, in this case, the brightness of image varies region by region, so that the display quality may deteriorate. Moreover, if the deterioration of the display quality tends to progress, the life of the display device may decrease. In addition, in the display device constituted by the four kinds of sub-pixels of red, green, blue, and white, a region with various circuits arranged therein around an image display surface is wider than that of a display device constituted by three kinds of sub-pixels, in some cases.
To solve the problems described above, it is an object of the present invention to provide a display device that reduces the deterioration of display quality, restrains the reduction in the life of the display device, and restrains the widening of the region around the image display surface.